Diagnostic Test Procedures

A diagnostic test procedure is:

- a systematic method of checking the functioning of a vehicle control system to determine if it is operating normally.
- a systematic method of analyzing and testing a vehicle control system to determine the source of a malfunction.

GUIDELINES FOR PERFORMING DIAGNOSTIC TEST PROCEDURES

All test procedures assume that Chrysler's DRBII diagnostic read-out box is being used.

To properly perform diagnostic testing of the Antilock-10 brake system using the test procedures, ALWAYS start with Test 1A. Starting with any other test may result in incorrect fault diagnosis.

^ Make sure the vehicle being tested has a fully charged battery.
^ Review Safety Instructions before performing the test procedures.
^ Perform a visual inspection of the connectors and wiring of the circuit being worked on prior to beginning a diagnostic test.
^ The tests are presented in modified flowchart form.
- The first two columns contain instruction statements. Perform each instruction in order. Perform each instruction as stated.
- The third column contains diagnostic questions. Answer each question with a "yes" or "no" answer.
- The fourth column contains repair or replacement instructions. Perform only the repair/replacement instruction(s) that follow from the "yes" or "no" answer to each question.
- To proceed from one process box to another, follow the direction of the lines between the boxes as indicated by the arrows.
- If a test is continued, an instruction is given in an arrow-shaped "box" to direct you to the next part or to another test.

NOTE: Tests are identified by a number/letter combination, such as Test 1A or Test 5C. To avoid confusion between the number 1 and the letter "I" and between the number 0 and the letter "C", no test identifications use the letters "I" or "C".

^ When testing voltage or continuity at the Controller - Antilock Brake System (CAB), use the terminal side (not the wire end) of the connector. Probing a wire through the insulation will damage it and eventually cause it to fail because of corrosion.
^ When probing a connector cavity, be careful not to spread the terminal. This could result in an intermittent problem.
^ Be careful when performing electrical tests so as to prevent accidental shorting of terminals. Such mistakes can damage fuses or components. Also, a second fault message could be set, making diagnosis of the original problem more difficult.
^ Use the DRBII voltmeter unless otherwise instructed to use an "external" voltmeter.

NOTE: Under no circumstances should a test lamp be used in place of a voltmeter.

^ Use the DRBII ohmmeter unless otherwise instructed to use an "external" ohmmeter. After each repair is completed, perform the Verification Test procedure (Test VER-1).